For those interested in the subject of conflicts of interest and the presidency, here is a good read from the Congressional Research Service:

Does federal law require the President to relinquish control of his or her business interests? Federal regulation of financial conflicts of interest is aimed at preventing opportunities for officials to personally benefit from influence they may have in their official capacity. As a general rule, public officials in the executive branch are subject to criminal penalties if they personally and substantially participate in matters in which they (or their immediate families, business partners or associated organizations) hold financial interests. However, because of concerns regarding interference with the exercise of constitutional duties, Congress has not applied these restrictions to the President. Consequently, there is no current legal requirement that would compel the President to relinquish financial interests because of a conflict of interest.